<!DOCTYPE html>
<html>
    <head>
        <title>frame</title>
    </head>
    <style>
        div{float: left;}
    </style>
    <body>
        <div>
        <iframe height="395px" width="400px" src="form_input.html">
        </iframe>
        </div>

        <iframe height="395px" width="400px" src="form_output.html">
        </iframe>
    </body>
</html>